Loss Estimation Method for Three-Phase AC Reactors of Two Types of Structures Using Amorphous Wound Cores in 400-kVA UPS

Abstract

We have developed a loss estimation method that is applicable to three-phase ac reactors using amorphous cores in a 400-kVA UPS. The method is based on measured the B-H curves and iron losses of the cores, modeled with magnetic simulations of a finite-element method considering the directions of the amorphous ribbon planes. The reactors are formed from wound cores. Two types of magnetic legs are proposed: structure A, toroidalshaped with slits, and structure B, sector prism-shaped cut from a wound core. Their unit volumes are shrunk by 9% and 19%, respectively, compared with that of a conventional silicon-steel core reactor. Both reactors have about half the total losses of the conventional silicon-steel core reactor, resulting in increased UPS efficiencies of up to 0.55%. The calculated iron losses at the pulse width modulation (PWM) carrier frequencies agree with measured losses within 10%. The accuracy of the loss estimation method for PWM-induced reactors is discussed. The method is confirmed to enable accurate design of a reactor for filtering in a high-efficiency inverter system.

Iron loss evaluation of three-phase inductor for three-phase PWM inverter

“…In this case, the terminal inductance, T A , T B , T C for A-phase, B-phase, and C-phase are expressed by (18) to (20), respectively.…”

“…Though, the authors have yet to evaluate coupled inductor core such as, three-phase inductor [14,15]. Onda et al have already evaluated and designed symmetrical three-phase inductor [18]. However, above mentioned inductor structure is not commonly used and not suitable for mass production.…”

Development of miniaturized AC reactors with lower-losses using amorphous wound cores in 400-kVA UPS

“…To design the reactors optimally, we adopted calculation models of iron losses in the amorphous wound cores on the basis of a technique for extracting the coordinate components of the B in accordance with the anisotropic B-H curves in the direction relative to the amorphous ribbon planes [5]. Overviews of individual models and an estimation method for reactor's losses are as follows.…”

“…This paper proposes a structure of amorphous core and constructing techniques suitable for physical properties of amorphous material by taking AC reactors for on-line 400-kVA UPS as subjects of an investigation (Section II). Overviews of the models and estimation method for reactor losses reported in [5] are presented (Section III). Subsequently, measured losses of the miniaturized reactors and UPS efficiencies are indicated (Sections IV).…”

Theoretical and Experimental Evaluation of the Temperature Distribution in a Dry Type Air Core Smoothing Reactor of HVDC Station

“…With the rapid development of numerical methods and computer performance, research on smoothing reactors is becoming more and more detailed, the loss and temperature distribution of reactor have also become research hotspots [6][7][8][9][10][11][12].…”